基于3D打印和接骨板标准件库数字化的股骨远端骨折内固定

Digital design of internal fixation for distal femoral fractures via 3D printing and standard parts database

目的探讨软件数字化设计结合3D打印技术在股骨远端骨折中导航置人标准件库接骨板进行内固定的方法。方法收集2013年8月至2014年6月莆田学院附属医院骨科收治的21例股骨远端骨折患者的cT扫描Dieom格式图像资料，分别导人Mimics软件予以三维重建、骨折复位。从标准件库中选择接骨板虚拟内固定，设计带钉道的导航模块。3D打印骨骼、接骨板、导航模块，进行现实骨骼模型内固定手术，导航放置接骨板、螺钉，观察导航模块卡位、板钉位置情况，以术后外观，CT扫描三维重建，三维配准后统计分析螺钉进、出钉点空间位置三维坐标值评价效果。结果共导航置入21块接骨板，180枚螺钉。21例骨骼模型术后均行cT扫描三维重建，结合外观，显示接骨板位置均与Mimics软件中模拟预设的一致，螺钉的进出钉点空间位置比较差异无统计学意义（P〉0．05），术前设计与现实手术实施效果高度相似。导航模块和相对应的股骨远端骨性结构贴合紧密，嵌合度良好，在应用时卡位及稳定性良好，可以很好指引接骨板放置、螺钉置人。术前与术后进、出钉点高度相关（X轴0．9892、Y轴0．9631、Z轴0．9617；X轴0．9893、Y轴0．9850、Z轴0．9410；P〈0．0001）。结论在导航模块的辅助下，股骨远端骨折标准件库接骨板内固定置入准确率高。

Objective To study the method of internal fixation by the navigation embedded plate from standard parts database for the distal femoral fractures based on digital design by Mimics software with 3D priming technology, and to explore its feasibility and accuracy. Methods A total of 21 cases with distal femoral fractures admitted into the Department of Orthopedics, Affiliated Hospital of Putian University were included in this study. Dicom format data of lamellar CT scanning was imported into Mimics software for 3D anatomical modeling and virtual fracture reduction. The steel plates was chose from standard parts database for virtual internal fixation, and to design the navigation module with screw. 3D printing skeleton, steel plates, navigation module, internal fixation implants were simulated based on the printed bones model. Locations of steel plates and screws were determined by the navigation module. Then the sticking effects of navigation module, screws position and postoperative appearance were observed. After second CT scan and 3D reconstruction, 3D registration was performed to obtain the data of the three-dimensional coordinate values of screws entrance points and piercing points to analyze the results. Results A total of 21 plates and 180 screws were placed with the assistance of navigation module. CT scanning and 3D reconstruction was performed in twenty-one cases of postoperative bone model. The position of plates was in high accordance with the digital design by Mimics software. There were no significant differences between spatial location of screw entrance points and piercing points. The real operation was quite consistent with preoperative design.Navigation module and the corresponding distal femur bony structure jointed closely. The sticking effects and stability of navigation module were good, which was able to guide placement of steel plates and screws. Conclusion These methods can enhance the accuracy of internal fixation of the standard parts database steel plate in distal femur fractures, with the assistance of navigation module.